Reciprocating pump for concrete

ABSTRACT

A reciprocating pump for concrete comprising a hollow body defining a concrete collection chamber with an inlet opening, concrete delivery pipes having a delivery opening communicating with said collection chamber, and pumping cylinders to pump concrete from a part of said collection chamber to said delivery pipes, and oscillating valve means to open and close alternatingly said inlet and delivery openings.

United States Patent Tarulli [541 RECIPROCATING PUMP FOR CONCRETE [72] Inventor: Luigi Tarulli, Viale Bovio- 12 Teramo, Italy 22 Filed: Dec. 14, 1970 [21] Appl.No.: 98,004

[30] Foreign Application Priority Data Dec. 22, 1969 Italy ..49s04 A/69 [52] US. Cl ..417/519, 417/900 [51] Int. Cl. ..F04b 7/00, F04b 15/02 [58] FieldofSearch ..417/5l6,517 ,'5l8,519,900; 251/173,175

[5 6] I References Cited UNITED STATES PATENTS V 8/1938 Campbell ..417/5l9 8/1943 Linstedt 3/1955 Saar .L ..251/l73 [4 1 Dec; 5, 1972 3,298,322 1/19 67, Sherrod ..4l7/5 17 3,198,123 8/1965 Wilkinson et .al... "417/900 3,181,469 5/1965 Schumann....... ..4 1 7/900 3,465,685 9/1969 Sherrod ..4 17/900 3,588,294 6/1971 Schlecht ..417/900 I FOREIGN PATENTS OR APPLICATIONS 1,803,819 6/1970 Germany ..417/5l7 1,182,583 1/1959 France ..25l/173 Primary Examiner-Henry F. Raduazo Att0meyGuido Modiaoand Albert Josif [57] ABSTRACT A reciprocating pump for concrete comprising a hollow body defining a concrete collection chamber with an inlet opening, concrete delivery pipes having a delivery opening communicating with said collection chamber, and pumping cylinders to pump concrete from a part of said collection chamber to said delivery pipes, and oscillating valve means to open and close v alternatingly said inlet and delivery openings.

5 Claims, 4 Drawing Figures P'ATE'N'TEDum 5:912

m r V ma am f6 INVEMTOR Luigi TARULLI BY M}: AGENT 1 RECIPROCATING PUMP FOR CONCRETE BACKGROUND OF THE INVENTION The present invention relates to or the like material.

The technical problems that are encountered in this technical field and which have not been up to now completely resolved by the known pumps for concrete are the following:

a. The obtainment of the continuity of concrete flow, since the discontinuity can increase the resistance in the tubing and cause the segregation of the components until annulling the pumpability of the concrete.

b. The obtainment of a satisfactory seal of the pump valve, since the lack of it aggravates the discontinuity, taking into. account that the dimensions of the inert materials (for example pebble gravel) influence the seal since they can, if considerable, impede the contact between the seal element and its relative seat.

c. The possibility of an easy and rapid cleaning of the pump at the end of the pumping, owing to'the rapidity of the setting of the cement used at present and the adherence and abrasivety of eventual residues.

SUMMARY OF THE INVENTION The general object of the present invention is to resolve in a technically efficient and economic manner the technical problems mentioned above.

A particular object is to produce a pump capable of pumping with continuity concrete also containing inert material of considerable dimensions.

Another particular object is to providevalve elements in the pump, having shape and trajectory of movement such to move away the inert materials of relatively large dimensions from the contact zone between the valve elements and their seats, or to crush such inert materials, in the case in 'whichthe removal of it has not occurred.

Another particular object is to produce a pump which internal walls are easily openable and accessible for an easy and efficient washing of it in away to notably diminish-the operating cost ofthe pump, due precisely to washing operations and in a way to notably. increase the life of the pump, which is a consequence of the efficient washing of it.

Another particular object is to produce a pump of simple and economic construction with a minimum number of component parts easily interchangeable, of long life, of efficient operation and of reduced production costs.

These and other objects of the invention which will appear from the description that follows, are achieved by a pump for concrete and like materials comprising a hollow body defining a concrete collection chamber, an inlet opening in said chamber for the introduction therein of the concrete, concrete delivery pipes having a delivery opening communicating with said collection chamber, and pumping cylinders suitable to pump the concrete contained in at least one part of said collection chamber towards said delivery pipes through said delivery opening and valve means suitable to open and close alternatingly said inlet and delivery openings, characterizedby the fact that said valve means comprise a shutter element, guide means for such shutter element defining a trajectory motion of said shutter element substantially extending in a tangential direction pumps for concrete BRIEF DESCRIPTION OF THE DRAWINGS Other characteristic advantages and objects of the invention will appear from the following detailed description .of a preferred embodiment of the invention illustrated by way of examplein the accompanying drawings in which: i 'FIG. 1 is a diagrammatic view in frontal elevation of the shown embodiment of The invention, partially in section, the sectional partbeing indicated with lines of greaterthickness;

FIG. 2 is a lateral view of the pump illustrated in FIG. lwith some parts omitted for the sake of clearness of the drawing and,

FIGS. 3 and 4 show a detail in cross-section of the shutter element in two different operating positions.

DESCRIPTION OF PREFERRED EMBODIMENT With reference to the drawingv thepump essentially comprises a main hollow body 1 defining the concrete collection chamber la. The concrete is introduced into the collection chamber 1a through a hopper 2 (FIG. 2)

*which bottom communicates with the collection chamber through an opening 2a, which extends according to an arcuated surface, extending substantially perpendicular to the plane of the drawing of FIG. 1.

The collection chamber 1a, as wellas the relative inlet opening 2a, are subdivided intotwo substantially symmetrical parts by a diaphragm or separation wall 2b. Upperly each. symmetric part of the collection chamber 1a, communicates withdelivery pipes 31, 31a through delivery openings 5a and 4a respectively. As best shown in FIG. 1 theinlet opening 2a is arranged adjacent and between the delivery openings 4a and 5a. The-delivery pipes both lead into a common delivery manifold 32. The valve 3 consists of two closure shutter elements having arcuated plate-like members 4 and 5, used to respectively open and close the delivery openings 40 and Saand the corresponding parts of the opening 2a. As shown in the left part of FIG. 1 the shutter members 4 and 5 have an operation edge extending in the closed position of the delivery openings,

somewhat inclined to the outer wall of the delivery pipes in the delivery direction of motion of the concrete. The shutter elements 4 and 5 are rigid with a support frame 3a revolvingly supported on a fulcrum 6 carried by the support plate 6a fixed on to the structure of the pump and which can be supported on the frame of a truck. The double-acting cylinder 7 transmits through an articulated joint an oscillating motion to the pivotal valve 3. i

To the lower parts of the main body which are opposite to the inlet and delivery openings 1, two pumping cylinders 8 and 9 are joined in which plungers or pumping pistons for concrete 10 and 11 slide, and which are actuated through rods 12 and 13 by pistons 14 and 15 hydraulically actuated within the cylinders 16 and 17 As visible from FIG. 1. the pivoting point 6 of the valve 3 is arranged opposite to the pumping cylinders with respect to the collection chamber and between the delivery pipes.

The hydraulic circuit which controls the cylinders 16 and 17 comprises a pump 18 which sends liquid under pressure to the distributor 19 from which ramify the pipes which carry the liquid under pressure, in a known way, towards the cylinders and 16 and the cylinder 7 controlling the valve 3.

The distributor 19 which may be of any conventional type produces the operative cycle electrically'or pneumatically or hydraulically, being controlled by switch means (not shown in'the drawing) responsive to the position of the various plungers or pistons and which can be of any known type. In the hydraulic circuit a hydro-pneumatic accumulator is also inserted which serves to provide an adequate closure or operating velocity to the valve 3. The seal of the valve 3 is laterally improved by the presence of resilient membranes 20 and 21 visible in FIGS. 3 and 4 provided on the side of each of the'faces of the closure shutter elements 4 and 5. The membranes 20 and 21 externally close respective cavities 20a and 20b provided in the shutter elements and hydraulically communicating with the cylinder 23, whereof the piston 22 is moved through the piston 24 controlled by the distributor 19. The hydraulic communication between the cylinder 23 and the cavities 20a and 21a is schematically indicated at 23a in FIG. 1. The membranes 20 and 21 can expand when the valve 3 is stopped to increase the seal and contract when such a valve 3 is moving in ordernot to hamper such a motion. The contraction and expansion of these membranes is controlled by the position of the piston 24 controlled in turn from the distributer 19.

The seal between the upperface of the closure elements 4 and 5 of the valve 3 and the fixed part of the valve body can .be produced also by means of membrane fixed on the above mentioned body which is controlled in the expansion and in the contraction by water delivered by the same plunger 22, thereby improving the seal. As show in'FIG. 3, thetransversal dimension of the shutter elements 4-and 5 is slightly smaller than the internal width of the collection chamber and the delivery openings and the sealing means are provided substantially along the central line of the lateral walls of the members 4 and 5.

The two cylinders 16 and 17 are connectedto each other-in a slave or servo-circuit by means of a pipe 25 which puts their upper chambers into communication.

' In such a way the liquid existing the upper chambers of such cylinders 16 and 17, alternately pass from one cylinder to the other depending upon the operation of them caused by the emission of liquid under pressure altematingly in the lower chambers of such cylinders 16 and 17.

The lower chambers of the cylinders 8 and 9 are connected to each other by means of pipes 26, and the water reservoir 28 by means of a pipe 27.

In such a way the lower chamber of such cylinders 8 and 9 are always filled with water circulating during their operation obtaining a continuous and automatic washing of the concrete pumping cylinders.

The group of cylinders 8, 9, 15 and 16 is removably connected for example by means of flanges 8a and 9a and relative screws to the body 1. The cylinders 8 and 9 each have a lug portion 290 rigidly fixed onto them, which is in turn hinged at 29 on to a lug portion 29b connected with the bodies 1 and to the pump support frame, not visible. The cylinders 8 and 9 are each arranged in alignment with one of the delivery pipes 31, 31a and converging to a common collector32.

In such a manner, after having unscrewed the screws or other fastening means from the flanges 8a and 9a-the groups of cylinders 8, 9, 16, 17 can be upwardly tilted about the fulcrum 29, as indicated with dotted lines in FIG. 2, sincethey are connected to the distributor 19 by means of flexible pipes.

The tilting about the fulcrum 29 may also not be simultaneous for the two cylinders 8 and 9. It is'also possible to provide rotation means about an axis perpendicular to that of the fulcrum 29 allowing to tilt each cylinder towards the outside (not shown in the drawing) or about any other rotation axis more constructively convenient. The overturned cylinders can operate in thisposition as during the pumping therefore obtaining a rapid and secure washing of the cylinders and of the main body, which remains lowerly opened.

The two delivery pipes 31 and 3la which ramify from the main body 1 lead by means of the collector 32 to the only delivery pipeline.

The preceding description relates to a pump having a vertical axis or nearly vertical extension, as such an arrangement besides being of greater efficiency does not require concrete seal elements nor valve control members.

Furthermore, with this arrangement, by virtue of its limited transverse dimension, the pump can be easily installed onto mobile cement mixer or trucks.

The arrangement with any inclination of the cylinder axes with respect to the horizontal is also suitable either with an autonomous functioning or in connection with a cement mixer.

The operating of the pump according to the invention will appear clear to a person skilled in the art, from the foregoing. Hereinafter such an operation is briefly summarized.

The chamber la is continually filled from the'hopper 2 through the opening 2a, of which one of the two parts is always open: In the position illustrated inFIG. l the piston 11 has reached its lower end stroke after its lowering stroke during which it favored the ingressing of the concrete into the collectionchamber 1a through the left half of the opening 2a, left open by the valve 3, producing a sucking effect. At the same time, the shutter element 5 maintains the right half of the opening 2a closed and while the piston 11 came down, the piston 10 goes up expelling the concrete from the right half of the collection chamber la into the delivery pipe 31, through the delivery opening 5a left open.

At the reaching of the upper end stroke of the piston 10 and at the lower end stroke of the piston 11, the valve 5, controlled by the cylinder 7 changes its position, with respect to that illustrated in FIG. 1, the shutter element 5 closing the delivery opening 5a and opening at the same time, the right part of the inlet opening 2a. At the same time, the shutter element 4 opens the delivery opening 4a and closes the left of the inlet opening 2a.

While the valve 3 is stopped, the distributor 19 con trolled in a known way, moves the piston 22 towards the left producing an expansion of the seal membrane 20, while at the beginning of the movement of the valve 3, the piston 22 is moved towards the left causing the contraction of the membrane 20 and allowing a move- I name 01 K I ment of the valve. However these sealing members are not to be considered as indispensible.

. The arcuated and substantially cutting edge shaped shape, allows the moving away of the ingredients with large dimensions or the crushing of them.

It will be appreciated that the momentum of the valve is substantial and contributes to the efficient functioning thereof.

During its operation the washing of the cylinders 8 and 9, being continuous and automatic, is bought about by means of the-water circuit 26, 27, 28 and once the pumping has been completed, the inside of the entire pump can be washed overturning the groups of cylinders 8 and 9 in the way described above allowing also an easy access in the collection chamber and in the delivery tubes.

Iclaim:

l. A pump for concrete or the like material comprising inlet and delivery openings for the concrete, delivery pipes downstreams of said delivery openings, a collection chamber between said inlet and said delivery openings, two pumping cylinders each having a port opening inside said collection chamber and pumping pistons for pumping the concrete from said collection chamber through said delivery openings into said delivery pipes, pivotal valve means having shutter elements arranged to alternatingly open and close said inlet and delivery openings and actuation means for operating said valve means and said shutter elements,

- wherein, according to the improvement, said inlet and delivery openings comprise an arcuated inlet opening arranged adjacent and between two of said delivery openings provided at the side of said collection chamber opposite to said pumping cylinders, 21 separation wall separating said collection chamber into two partial chambers arranged simmetrically with respect to said inlet opening, said shutter elements each having an arcuated substantially plate-like member movable tangentially to said inlet opening and substantially transversely to said delivery pipes, said plate-like members being arranged at a distance from one another substantially corresponding to the half of'thearcuated length of said arcuated inlet opening to alternatingly I open and close half of said arcuated inlet opening, and

wherein the pivotal point of said pivotal valve means is arranged opposite to the pumping cylinders with respect to said collection chamber and between said delivery pipes.

2. A pump according to claim 1, wherein said pumping cylinders are each arranged in alignment with one of said delivery pipes and converging to a common collector of said delivery pipes for the pumped concrete.

tion sealin means are r vided subs ntiall alon the central lin of said latei ai walls of sa i c l arcu ated p%atelike members.

5. A pump according to claim 1, wherein said pumping cylinders are hingedly arranged on said collection chamber adjacent said ports opening inside said collection chamber. 

1. A pump for concrete or the like material comprising inlet and delivery openings for the concrete, delivery pipes downstreams of said delivery openings, a collection chamber between said inlet and said delivery openings, two pumping cylinders each having a port opening inside said collection chamber and pumping pistons for pumping the concrete from said collection chamber through said delivery openings into said delivery pipes, pivotal valve means having shutter elements arranged to alternatingly open and close said inlet and delivery openings and actuation means for operating said valve means and said shutter elements, wherein, according to the improvement, said inlet and delivery openings comprise an arcuated inlet opening arranged adjacent and between two of said delivery openings provided at the side of said collection chamber opposite to said pumping cylinders, a separation wall separating said collection chamber into two partial chambers arranged simmetrically with respect to said inlet opening, said shutter elements each having an arcuated substantially plate-like member movable tangentially to said inlet opening and substantially transversely to said delivery pipes, said plate-like members being arranged at a distance from one another substantially corresponding to the half of the arcuated length of said arcuated inlet opening to alternatingly open and close half of said arcuated inlet opening, and wherein the pivotal point of said pivotal valve means is arranged opposite to the pumping cylinders with respect to said collection chamber and between said delivery pipes.
 2. A pump according to claim 1, wherein said pumping cylinders are each arranged in alignment with one of said delivery pipes and converging to a common collector of said delivery pipes for the pumped concrete.
 3. A pump according to claim 1, wherein said arcuated plate-like members of said shutter element each have an operation edge extending, in the closed position of said delivery openings, into said delivery pipes substantially inclined to the outer wall of said delivery pipes in the delivery direction of motion of the concrete.
 4. A pump according to claim 1, wherein said arcuated plate-like members of said shutter elements each have a transversal dimension slightly smaller than the inner width of said collection chamber and said delivery openings and wherein expansion and contraction sealing means are provided substantially along the central line of said lateral walls of said arcuated plate-like members.
 5. A pump according to claim 1, wherein said pumping cylinders are hingedly arranged on said collection chamber adjacent said ports opening inside said collection chamber. 